1. Field of the Invention
The invention relates to an image-guided surgery system.
2. Description of Related Art
An image-guided surgery system of this kind is known from United States patent specification U.S. Pat. No. 5,389,101.
An image-guided surgery system is used to visualize a position of a surgical instrument in an operating area within the body of a patient for a surgeon during surgery. Images, such as CT or MRI images, are made of the patient prior to surgery. The image-guided surgery system includes a position-measuring system for measuring the position of the surgical instrument. The image-guided surgery system also includes a computer for deriving corresponding positions in a relevant image from the positions of the surgical instrument measured. During surgery the position measuring system measures the position of the surgical instrument relative to the patient and the computer calculates the position in such a prior image which corresponds to the measured position of the surgical instrument. The prior image is then displayed on a monitor, together with the actual position of the surgical instrument. The surgeon can see the position of the surgical instrument in the operating area in the image on the monitor, without him or her seeing the surgical instrument directly. The surgeon can thus observe the image displayed on the monitor so as to see how to move the surgical instrument in the operating area without substantial risk of unnecessary damaging of tissue, and notably without risk of damaging of vital parts.
An image-guided surgery system of this kind is used, for example in neurosurgery in order to show the surgeon accurately where the surgical instrument is situated in the brain during a cerebral operation.
Using the known image-guided surgery system it is difficult to position the instrument with one end in a desired position. In order to move the instrument to the desired position, it is necessary to move it whereas at the same time the image showing the position of the surgical instrument relative to the patient must be observed so as to determine whether the desired position has been reached. It has been found that accurate positioning of the instrument requires a substantial amount of training and that these operations remain time consuming still.